TORONTO--Migrant thriller "Desierto" relies on gripping action to send a sharp message about heated rhetoric sowing the seeds of violence, but the film's star Gael García Bernal has no problem distilling it into words. "The main problem right now with that subject matter is that we view it as a problem. It's not," said the Mexican actor, who had his own visa troubles getting to the Toronto film festival for the movie premiere. "Immigration is something that has happened since humanity began." Europe is struggling to deal with its biggest migrant crisis since World War Two amid harrowing images of drowned children and the rise of anti-immigration populists. Meanwhile front running U.S. presidential candidate Donald Trump proposes mass deportations and a wall to stem the flow across its southern border. "There is a discourse of hate," García Bernal said of the debates about securing borders and cracking down on undocumented workers. In "Desierto" (Desert), his character Moises faces the personification of that hate in murderous vigilante Sam, played by Jeffrey Dean Morgan, who whittles down a group of people seeking to cross the border with the help of a long-range rifle and a ferocious dog. "This is what happens when somebody validates that conversation, that discourse," García Bernal said. "That's how genocide begins, that's how civil wars start, by validating that ignorant, repulsive, bigoted discourse." García Bernal has traveled this path before, following a typical migrant route from central America to the United States in the 2013 documentary "Who Is Dayani Cristal?" while seeking the identity of an anonymous man found dead in the Arizona desert. Director Jonás Cuarón said he stripped Moises, Sam and the other travelers of a back story in order to focus attention on the perilous journey across an unforgiving landscape. "The desert doesn't have those biases that we have," he said. "To him everyone is the same. "It's beautiful but also doesn't care about either of the characters, they're all the same, they're stripped down and brought down to their most human level," he said of the desert.